(772g) Development of LIBS Sensor for Sub-Surface CO2 Leak Detection in Carbon Sequestration

To ensure the success of USDOE’s CCS program it is important that the carbon dioxide that is injected underground for storage remains there permanently (99% permanence over 1000 years). In fact, the integrity of the storage can be ensured by monitoring for CO₂ leakage, and injection sites are the logical places to perform such monitoring. The sub-surface environment is notoriously harsh, with large potential mechanical, thermal, and chemical stresses, making long-term stability and survival a challenge to any potential in situ monitoring method. The laser induced breakdown spectroscopy (LIBS) has been demonstrated as a promising technology for chemical monitoring of harsh environments and hard to reach places. LIBS has a real-time monitoring capability and can be used for the elemental and isotopic analysis of solid, liquid, and gas samples. The flexibility of the probe design and the use of fiber-optics has made LIBS particularly suited for remote measurements. Our experiments using a stainless steel high-pressure cell demonstrated that the LIBS is a suitable technique to perform measurements in high-temperature and high-pressure (HTHP) environment, which makes it attractive for downhole measurements. The discussion will include the progress in fabricating a compact, robust, and simple LIBS sensor and distribution of many laser spark sources across a wide area for widespread subsurface leak detection.